What is a better mBaaS that supports offline sync and caching? - offline

What is a better mBaaS that supports offline sync and caching?
I am evaluating several mBaaS solutions for my hybrid mobile app under development. I looked at Kinvey, Kii, buddy, and Telerik BackEnd platform. I have also came across some open source solutions like openmobster and dreamfactory. I am looking to store data in sql-lite on mobile app and then sync it back with an online data store. Kinvey has this support, but their pricing model (per user) is not suitable in my scenario. I can see that openmobster does this but, how is what I need to understand? Can I host in on Azure VM or something? Also please suggest if there is any other solution commercial/open source capable of doing offline sync and caching with push notifications and data storage?

DreamFactory could be a good fit for your scenario. It is open source and comes with a full 30 days of free support. After which it's only like $25/month for a developer account - and this isn't even a requirement to use its product. It's specifically a support package.
To address your question a little more in-depth... I don't believe DreamFactory supports offline syncing at the moment, though they plan to very soon. In regards to sql-lite, DreamFactory's (DSP) product has a built in sql-lite driver to connect to that DB. However, it hasn't been tested enough for them to say it is a fully supported RDBMS. One of the beautiful things about DreamFactory is you're able to host the DSP (DreamFactory Service Platform) on Azure and Amazon EC2 instances (cloud solutions), host locally on your own server, or even use its own free hosted edition!
I would definitely take a little time to look into DF. It doesn't seem to me like you have much to lose. Especially, considering it's a free open-source product!
Feel free to ask me any questions you may have about DreamFactory!
-Mark

Related

What is the difference between 'SAS' and 'Salesforce'

I would be starting ft in one company, where i was been told that the application is developed using 'Sas' and 'salesforce'. What is the difference between two?
And which are recommended online resource which I can use to learn more about it.
SAS is software for statistical analysis. If your company/job description doesn't look like working with large sets of data & complex reporting that's probably not it.
They probably mean SaaS (Software as a Service) model, also known as "the cloud", cloud computing etc. You write the program (or use / modify existing one) but you don't buy servers, worry about network connection, electricity costs, load balancing (spikes in traffic will not cause your website to go down). Many apps operate in this model. Microsoft's Azure cloud (or even online wersions of MS Office). There's Siebel Oracle on Demand CRM, Microsoft Dynamics, SAP I think also has SaaS offering...
It's a big topic, I'm simplifying a lot here. And then there are Platform as a Service things too (PaaS) where they give you "just" the hosting etc but no base application to build on top of. You write everything you need from scratch and upload it. Think Heroku or Amazon Web Services (AWS).
Salesforce is "just" one more SaaS application. You start with base application & database, similar to all other clients in the world. You can install plugins to it (some free, some paid), configure it yourself, write custom code if your functionality is too complex... You can do a lot with just clicks & drag & drop but if you need to code stuff then JavaScript (for client-side) and Apex (for server-side) will be your friend. Apex is bit similar to Java.
Where to start... Trailhead is good source of self-paced trainings. You can sign up for a free Salesforce Developer Edition (has almost all features as the paid one but limited storage space), try to pass some courses... Or in SF help&training there should be tons of videos (actually in that link whole left menu "getting started with salesforce" might be good).

Google Cloud - Stack recommendation for Tomcat/PostgreSQL/HTTPS/SFTP site?

This is my first attempt at looking into cloud hosting and I'm feeling like a complete idiot. I have always had my own dedicated server with which I would would remote in and install/manage everything myself. So this cloud thing is completely new for me. I just can't seem to grasp basic things... like how I would get Tomcat and PostgreSQL installed in a way that they could talk to each other or get my domain and SSL cert on there, etc.
If I could just get a feel for where I should start, then I could probably calculate my costs and jump into the free trial where hopefully things will click for me.
Here are my basic, high-level requirements...
My web app running in Tomcat over HTTPS
Let's say approximately 1,000 page views per day
PostgreSQL supporting my web app.
Let's say approximately 10GB database storage
Throughout the day, a fairly steady stream of inbound SFTP data (~ 100MB per day)
The processing load on the app server side should be fairly light. The heaving lifting will be on the DB side sorting through and processing lots of data.
I'm having trouble figuring out which options I would install and calculating costs. If someone could help me get started by saying something like "You would start with a std-xyz-med server, install ABC located here at http://blahblah, then install XYZ located at http://XYZ.... etc.. etc. You can expect to pay somewhere around $100-$200 per month"....
Thoughts?
I would be eternally grateful. It seems like they should have some free sales support channel to ask someone at Google about this, but I don't see it.
Thank You!
I'll try to give you some tips where to start looking.
I will be referring to some products, here are the links
If you want to stick to your old ways, you can always spin up an instance on Compute Engine and set it up the same way you did before, these are just regular virtual machines. For some use cases this is completely valid.
You can split different components of your stack to different products:
For example, if your app is fine with postgresql, you can spin up a fully managed service in Cloud SQL, which might make it easier to manage backup or have several apps access the same db.
Alternatively, have a look at the different DB offerings to see if any of them matches your needed workload better. Perhaps have a look at BigQuery?
If you want to turn your app into a microservice, which is then easier to autoscale and is more fault tolerant, have a look at App Engine. That way you don't need to manage a virtual machine. The docs here will lead you through some easy to follow examples on how to set up SSL.
For the services to talk to each other, refer to docs of the individual components. It's usually very simple.
With pricing, try https://cloud.google.com/products/calculator/
Things like BigQuery have different pricing models - you don't pay for server uptime, but for amounts of data stored & processed with your queries.

How to convert a WAMP stacked app running on a VPS to a scalable AWS app?

I have a web app running on php, mysql, apache on a virtual windows server. I want to redesign it so it is scalable (for fun so I can learn new things) on AWS.
I can see how to setup an EC2 and dump it all in there but I want to make it scalable and take advantage of all the cool features on AWS.
I've tried googling but just can't find a simple guide (note - I have no command line experience of Linux)
Can anyone direct me to detailed resources that can lead me through the steps and teach me? Or alternatively, summarise the steps in an answer so I can research based on what you say.
Thanks
AWS is growing and changing all the time, so there aren't a lot of books to help. Amazon offers training that's excellent. I took their three day class on Architecting with AWS that seems to be just what you're looking for.
Of course, not everyone can afford to spend the travel time and money to attend a class. The AWS re:Invent conference in November 2012 had a lot of sessions related to what you want, and most (maybe all) of the sessions have videos available online for free. Building Web Scale Applications With AWS is probably relevant (slides and video available), as is Dissecting an Internet-Scale Application (slides and video available).
A great way to understand these options better is by fiddling with your existing application on AWS. It will be easy to just move it to an EC2 instance in AWS, then start taking more advantage of what's available. The first thing I'd do is get rid of the MySql server on your own machine and use one offered with RDS. Once that's stable, create one or more read replicas in RDS, and change your application to read from them for most operations, reading from the main (writable) database only when you need completely current results.
Does your application keep any data on the web server, other than in the database? If so, get rid of all local storage by moving that data off the EC2 instance. Some of it might go to the database, some (like big files) might be suitable for S3. DynamoDB is a good place for things like session data.
All of the above reduces the load on the web server to just your application code, which helps with scalability. And now that you keep no state on the web server, you can use ELB and Auto-scaling to automatically run multiple web servers (and even automatically launch more as needed) to handle greater load.
Does the application have any long running, intensive operations that you now perform on demand from a web request? Consider not performing the operation when asked, but instead queueing the request using SQS, and just telling the user you'll get to it. Now have long running processes (or cron jobs or scheduled tasks) check the queue regularly, run the requested operation, and email the result (using SES) back to the user. To really scale up, you can move those jobs off your web server to dedicated machines, and again use auto-scaling if needed.
Do you need bigger machines, or perhaps can live with smaller ones? CloudWatch metrics can show you how much IO, memory, and CPU are used over time. You can use provisioned IOPS with EC2 or RDS instances to improve performance (at a cost) as needed, and use difference size instances for more memory or CPU.
All this AWS setup and configuration can be done with the AWS web console, or command-line tools, or SDKs available in many languages (Python's boto library is great). After learning the basics, look into CloudFormation to automate it better (I've written a couple of posts about that so far).
That's a bit of the 10,000 foot high view of one approach. You'll need to discover the details of each AWS service when you try to use them. AWS has good documentation about all of them.
Depending on how you look at it, this is more of a comment than it is an answer, but it was too long to write as a comment.
What you're asking for really can't be answered on SO--it's a huge, complex question. You're basically asking is "How to I design a highly-scalable, durable application that can be deployed on a cloud-based platform?" The answer depends largely on:
The specifics of your application--what does it do and how does it work?
Your tolerance for downtime balanced against your budget
Your present development and deployment workflow
The resources/skill sets you have on-staff to support the application
What your launch time frame looks like.
I run a software consulting company that specializes in consulting on Amazon Web Services architecture. About 80% of our business is investigating and answering these questions for our clients. It's a multi-week long project each time.
However, to get you pointed in the right direction, I'd recommend that you look at Elastic Beanstalk. It's a PaaS-like service that abstracts away the underlying AWS resources, making AWS easier to use for developers who don't have a lot of sysadmin experience. Think of it as "training wheels" for designing an autoscaling application on AWS.

Django hosting on ep.io

is there someone who has expirience in hosting django applications on ep.io?
Waht are the pros/cons on it?
I'm currently using ep.io, I'm still in development with my app but I have an app deployed and running.
When you use a service like this you go into it knowing that it isn't going to be the perfect solution for every case. Knowing the pros and cons before hand will help set your expectations so that you aren't disappointed later on.
ep.io is still very young and I believe still in beta, and isn't available to the general public. To be totally fair to them, it is still a work in progress and some of these pros and cons may change as they roll out new features. I will try and come back and update this post as the new versions become available, and my experience with the service continues.
So far I am really pleased with what they have, they took the most annoying part of developing an application and made it better. If you have a simple blog app, it should be a breeze to deploy it, and probably not cost that much to host.
Pros:
Server Management: You don't have to worry about your server setup at all, it handles everything for you. With a VPS, you would need to worry about making sure the server is up to date with security patches, and all that fun stuff, with this, you don't worry about anything, they take care of all that for you.
deployment: It makes deploying an app and having it up and running really quickly. deploying a new version of an app is a piece of cake, I just need to run one maybe two commands, and it handles everything for me.
Pricing: you are only charged for what you use, so if you have a very low traffic website, it might not cost you anything at all.
Scaling: They handle scaling and load balancing for you out of the box, no need for you to worry about that. You still need to write your application so that it can scale efficiently, but if you do, they will handle the rest.
Background tasks: They have support for cronjobs as well as background workers using celery.
Customer support: I had a few questions, sent them an email, and had an answer really fast, they have been great, so much better then I would have expected. If you run your own VPS, you really don't have anyone to talk to, so this is a major plus.
Cons:
DB access: You don't have direct access to the database, you can get to the psql shell, but you can't connect an external client gui. This makes doing somethings a little more difficult or slow. But you can still use the django admin or fixtures to do a lot of things.
Limited services available: It currently only supports Postgresql and redis, so if you want to use MySQL, memcached, mongodb,etc you are out of luck.
low level c libs: You can't install any dependencies that you want, similar to google app engine, they have some of the common c libs installed already, and if you want something different that isn't already installed you will need to contact them to get it added. http://www.ep.io/docs/runtime/#python-libraries
email: You can't send or recieve email, which means you will need to depend on a 3rd party for that, which is probably good practice anyway, but it just means more money.
file system: You have a more limited file system available to you, and because of the distributed nature of the system you will need to be very careful when working from files. You can't (unless i missed it) connect to your account via (s)ftp to upload files, you will need to connect via the ep.io command line tool and either do an rsync or a push of a repo to get files up there.
Update: for more info see my blog post on my experiences with ep.io : http://kencochrane.net/blog/2011/04/my-experiences-with-epio/
Update: Epio closed down on May 31st 2012

Should I use CouchDB or SimpleDB?

I'm creating an application that will be hosted on amazon EC2 and a lot of the data that'll be saved is more document oriented (as well as saving tweets and such related to those documents).
Right now I'm at a crossroads... should I use simpleDB or couchDB? Whats the pros/cons of using either? Should I just try both for a month and decide then?
You may find the the article Amazon SimpleDB and CouchDB Compared to be useful.
I've also found that MongoDB gives excellent performance.
Keep in mind that if your code lives in EC2, SimpleDB will be presumably hosted in the same data center that your code is, which would give SimpleDB a lower latency than CouchDB for requests from an EC2 server. Also, Amazon doesn't charge you bandwidth costs between EC2 and SimpleDB.
I would expect SimpleDB to be both faster and cheaper for code running in EC2, for those reasons.
SimpleDB is hosted and maintained by Amazon for you, CouchDB is all up to you. That's the big difference.
I would absolutely do some benchmark of the two solutions with your own use-case, if that's possible, i.e. if you can build a reasonable subset of your application to run on either databases (they have quite different APIs so this might not be easy).
If you develop in .Net environment there's an excellent lib for SimpleDB called Simple Savant which really eases the integration..
I've built some live solutions using SimpleDB and it works very well, especially with a caching layer in front of it (cf memcached et al). However I've recently started scoping out a new project and have decided to move to CouchDB for the primary reason of having control over the data.
As your commitment to SimpleDB grows, it gets harder and harder to migrate away to anything else (ah the joys of vendor lock in) and, frankly, that just isn't great for our business.
I remain a strong evangelist of cloud tech, and Amazon in particular, but I feel a lot better running couchdb on EC2 than I do with SimpleDB.
Roger